1) Field of the Invention
This invention pertains to the field of optical device testing and in particular to an apparatus and method for facilitating inspection of the surfaces of optical devices on an optical module.
2) Background of the Related Art
Optical devices combined with electronics are increasingly being used in communication and information systems. It is important to inspect the surfaces of the optical devices after final assembly onto on optical module to insure that the module will perform as expected.
Inspection of the optical device surfaces is typically performed at one or more optical inspection stations in an test circuit on an optical bench or platform. An inspection station may typically include a microscope or an electronic imaging device or camera for inspecting the optical device(s). Each optical device surface is manually aligned with an optical device interface at one or more inspection stations and then inspected. A connector may be provided between an optical device interface of the inspection station and an optical device to be inspected.
Unfortunately, manual alignment is labor-intensive and somewhat difficult. A microscope or optical camera is typically heavy, rigid and fixed with little or no alignment flexibility. Likewise, the optical module is often heavy and rigid. Also, the degree of precision required for optical alignment precludes the use of flexible connectors between the microscope and the optical device.
Often during the alignment process, one or more optical device surfaces inadvertently strike against the platform or inspection apparatus, damaging the optical surface. This can necessitate costly repairs or even cause the module to be wasted.
For example an optical module can cost $50,000 or more, and it is not uncommon for repairs caused by damage to an optical device during inspection to amount to $10,000.
Accordingly, it would be advantageous to provide an apparatus and method for easily bringing optical device surfaces reliably into alignment with inspection stations. It would also be advantageous to provide an apparatus and method which provides an extra degree of freedom of movement when aligning an optical inspection station with an optical device on an optical module. It would further be advantageous to provide an automated apparatus and method which reduces the amount of labor involved in the process. Other and further objects and advantages will appear hereinafter.